TNFAIP6 promotes invasion and metastasis of gastric cancer and indicates poor prognosis of patients

TNFα-stimulated gene-6 (TNFAIP6) plays an important role in the prognosis of many tumors. Our objective was to investigate the clinical and prognostic value of TNFAIP6 expression in gastric cancer (GC) patients. Here, we investigated the expression of TNFAIP6 in GC tissues using western blotting and immunohistochemistry and the association between TNFAIP6 expression and the prognosis and clinicopathological parameters of GC patients. Our results revealed that the expression of TNFAIP6 was higher in GC tissue than in normal gastric tissue, and the levels were positively correlated with the depth of tumor invasion (P = 0.010), tumors with lymph node metastasis (P = 0.000) and TNM stage (P = 0.003) of GC patients. Moreover, the results revealed that patients with high TNFAIP6 expression exhibited poorer overall survival than those with low TNFAIP6 expression (P = 0.037). Additionally, knockdown of TNFAIP6 inhibited the proliferation, invasion and metastasis of GC cells in vitro. High TNFAIP6 expression was associated with the depth of tumor invasion, lymph node metastasis, TNM stage and poor prognosis of GC patients, suggesting that TNFAIP6 may serve as a novel indicator of the prognosis and as a treatment target of GC.

Previous Exposure to the Fish Parasite Anisakis as a Potential Risk Factor for Gastric or Colon Adenocarcinoma

Anisakiasis is a global disease caused by consumption of raw or lightly cooked fish contaminated with L3 Anisakis spp. larvae. High rates of parasitization of fish worldwide make Anisakis a serious health hazard. In fact, anisakiasis is a growing disease in countries such as Spain, Italy, and Japan, where consumption of raw/marinated fish is high. Some parasitic infections have been recognized as a causative factor for human cancer. Suggested mechanisms include chronic inflammation elicited by the parasite, and a possible tumorigenic effect from certain parasitic secretions. Anisakis can produce persistent local inflammation and granuloma, and larvae have been incidentally found in gastrointestinal (GI) tumors. Our aim was to discover possible differences in the prevalence of unnoticed or asymptomatic previous Anisakis infection in GI cancer patients compared with healthy individuals. Serum levels of specific antibodies against Anisakis antigens were used as a reliable marker of previous contact with their larvae. Ninety-four participants without a previous history of Anisakis infection were prospectively allocated into 1 of 2 groups: 47 patients with GI cancer and 47 controls. Specific IgE, IgA1, and IgG1 against the Anisakis recombinant antigens Ani s 1, Ani s 5, Ani s 9, and Ani s 10 were determined by an ELISA assay. The ratio of positivity to sIgA1, rAni s 1, or rAni s 5 was significantly higher in the cancer patients than in the controls (38.30% vs 6.38%, P < 0.001) and (42.55% vs 10.64%, P < 0.001, respectively). When disaggregated by type of tumor, the patients with gastric cancer showed a higher proportion of positive results for sIgA1 to rAni s 1 (P < 0.001), whereas a higher proportion of colon cancer patients were shown to be positive for sIgA1 to both rAni s 1 (P < 0.05) and rAni s 5 (P < 0.01). Earlier Anisakis infection might be a risk factor for the development of stomach or colon cancer.

Low-positive antibody titer against Helicobacter pylori cytotoxin-associated gene A (CagA) may predict future gastric cancer better than simple seropositivity against H. pylori CagA or against H. pylori

BACKGROUND

To investigate the IgG antibody titer against Helicobacter pylori CagA as a risk factor for future noncardia gastric cancer.

METHODS

A nested case-control study was done in the longitudinal cohort of atomic bomb survivors using stored sera before diagnosis (mean, 2.3 years). Enrolled were 299 cancer cases and 3 controls per case selected from cohort members matched on age, gender, city, and time and type of serum storage and countermatched on radiation dose.

RESULTS

H. pylori IgG seropositive with CagA IgG low titer was the strongest risk factor for noncardia gastric cancer [relative risk (RR), 3.9; 95% confidence interval (95% CI), 2.1-7.0; P < 0.001], especially for intestinal-type tumor (RR, 9.9, 95% CI, 3.5-27.4; P < 0.001), compared with other risk factors, H. pylori IgG seropositive with CagA IgG negative (RR, 2.2; 95% CI, 1.3-3.9; P = 0.0052), H. pylori IgG seropositive with CagA IgG high titer (RR, 2.0; 95% CI, 1.3-3.2; P = 0.0022), chronic atrophic gastritis (RR, 2.4; 95% CI, 1.8-3.3; P < 0.001), current smoking (RR, 2.3; 95% CI, 1.4-3.5; P < 0.001), or radiation dose (RR, 2.1; 95% CI, 1.2-3.1; P = 0.00193). Current smoking showed significantly higher risk for diffuse-type than intestinal-type tumors (P = 0.0372). Radiation risk was significant only for nonsmokers, all noncardia, and diffuse-type gastric cancers.

CONCLUSIONS

A low CagA IgG titer is a useful biomarker to identify a high-risk group and it also provides a clue to understanding host-pathogen interaction.

Giardia lamblia trophozoites in gastric biopsies

To assess the prevalence of gastric giardiasis in gastric biopsies of patients with carcinoma stomach and in patients taking treatment for duodenal ulcer. Gastric biopsy specimens from 54 patients of carcinoma stomach and 100 antral biopsies from patients taking treatment for duodenal ulcer were included in the study. Sections were stained with haematoxylin and eosin, methylene blue and May Grunwald-Giemsa stains and examined for presence of Giardia lamblia trophozoites. Eight out of 54 (14.9%) biopsies of gastric carcinoma patients harboured trophozoites of Giardia lamblia. Associated H. pylori infection was present in all biopsies (8/8; 100%). Atrophy and intestinal metaplasia was present in 62.5% (5/8) and 25% (2/8) cases respectively. Sections from seven out of 35 patients (20%) taking treatment for duodenal ulcer showed presence of G. lamblia. H. pylori infection, gastritis and atrophy were found in 85.7% (6/7), 71.4% (5/7) and 28.6% (2/7) cases respectively. First gastric biopsy in these patients was negative for G. lamblia but 2nd and 3rd biopsies were positive. A careful search for G. lamblia trophozoites should be made while examining the gastric biopsies, especially in patients with carcinoma stomach, intestinal metaplasia, atrophic gastritis and those taking treatment for duodenal ulcer. This may help in indirect diagnosis of clinically unsuspected cases of intestinal giardiasis and may explain persistence of vague upper gastrointestinal tract (UGIT) symptoms despite clearance of H. pylori in patients on anti-ulcer therapy.

Toxoplasma infection and cell free extract of the parasites are able to reverse multidrug resistance of mouse lymphoma and human gastric cancer cells in vitro

A large number of compounds are known to reduce the ATP-dependent efflux pump activity of multidrug resistant (mdr) tumor cells. Here we report that an infection of cancer cells with T. gondii reduced the multidrug resistance of the tumour cells against cytostatic drugs. Two mouse lymphoma cell lines (Mdr L 5718 and Par 5718) were infected with Toxoplasma gondii in vitro and the reduction of efflux pump activity of the cells was measured. The drug accumulation (Rhodamin-123) was increased in the infected mdr cell lines compared with non- infected mdr-cells, and no effect was shown after infection of the parental cell line. The same effect was also achieved by incubation of Mdr-tumor cells with cell lysate of Toxoplasma gondii. Mdr-1-gene expression was reduced in the infected cell lines 48 hours after infection. Co-cultivation of Toxoplasma gondii with mdr cell lines separated by a microfilter from tumor cells was performed, but this cocultivation did not change the mdr efflux activity. The effect of Toxoplasma gondii infection on the efflux pump activity and mdr-1 gene expression was also examined in the human gastric cancer cells. A sensitization of resistant gastric cancer cells was also achieved by parasite infection. This phenomenon is an evidence that a reduction of resistance in tumor cells can be achieved by a natural parasite infection. It is as yet unclear whether an active infection or another substance of T. gondii is responsible for this phenomenon.

[Apropos of 1 case of hepatogastric fascioliasis in Cape Verde]

The authors report a case of Fascioliasis sp. distomiasis with a double hepatic and gastric location primitively associated with a gastric cancer metastazed to the liver. The parasitic origin of the lesions suspected from the histological specimen of the gastric biopsy (the presence of eggs) was confirmed by serology with the presence of the arc 2 specific to immunoelectrophoretic analysis, while the parasitological examination of the stools was always negative. The patient grew well after a day's cure of triclabendazole (375 mg x 2). Although the ectopic locations of Fascioliasis are classic, they are usually in the abdominal wall, less frequently in the gastric or colic wall. The fact that the contamination originated on the Cape Verde is indiscutable, since the patient had never left the island. It is the 5th case described in medical literature, thus confirming the presence of Fasciola hepatica (or gigantica) on the islands of the Cape Verde, whose population is of both Portuguese and African origin and has kept the eating habits of the former colonial power (Portugal is a zone of high endemicity for human fascioliasis). It would be interesting to look for Limnaea and contaminated bovine on the Cape Verde islands.

The morphogenesis of a papillomatous gastric polyp in the crab-eating monkey (Macaca fascicularis)

The histopathology of gastric papillomas in 17 crab-eating monkeys from Indonesia and Malaysia was investigated. The changes in the affected mucosa consisted of papillomatous proliferation with accidental heterotopia, desquamation or necrosis of the epithelium associated with eggs or adults of the small nematode Nochtia nochti, inflammatory cell infiltration and haemorrhage or oedema and fibrosis. The primary pathogenic effect of this parasite was due to its irritant action on the gastric mucosa. Hyper-regeneration, with a downward shift of the proliferating zone in the gastric gland and an inflammatory process, appeared to play a significant role in the morphogenesis of this lesion. It is concluded that the gastric papilloma associated with Nochtia nochti in the monkey is a parasitic inflammatory polyp.